/* css reset 变成白纸 */
/* 不推荐 性能不太好 */
/* *{
    margin: 0;
    padding: 0;
} */
html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, embed, 
figure, figcaption, footer, header, hgroup, 
menu, nav, output, ruby, section, summary,
time, mark, audio, video {
	margin: 0;
	padding: 0;
	border: 0;
	font-size: 100%;
	font: inherit;
	vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure, 
footer, header, hgroup, menu, nav, section {
	display: block;
}
body {
	line-height: 1;
}
ol, ul {
	list-style: none;
}
blockquote, q {
	quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
	content: '';
	content: none;
}
table {
	border-collapse: collapse;
	border-spacing: 0;
}


/* 业务代码 */
body{
    height: 100vh;
    width: 100vw;
    background: radial-gradient(circle at center,#fff ,#fff 50%,#aaa );
}
.baymax{
    width: 50%;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-40%);
    background-color: black;
    border-bottom: 1.5em solid #000;
}
.baymax:before{
    content: "";
    width: 12em;
    height: 12em;
    border-radius: 50%;
    /* display: block; */
    position: absolute;
    top: -6em;
    left: -9em;
    background: linear-gradient(to bottom,#efefef,#fff 50%,#000 50%,#000);
    background-size: 200% 200%;
    background-position: 0% -100%;
    animation: blink 6s infinite;
}
.baymax:after{
    content: "";
    width: 12em;
    height: 12em;
    border-radius: 50%;
    /* display: block; */
    position: absolute;
    top: -6em;
    right: -9em;
    background: linear-gradient(to bottom,#efefef,#fff 50%,#000 50%,#000);
    background-size: 200% 200%;
    background-position: 0% -100%;
    /* animation: blink 6s .1s infinite; */
    animation-delay: .1s;
    animation-name: blink;
    animation-duration: 6s;
    animation-iteration-count: infinite;
}
@keyframes blink{
    0%,50%{
        background-position: 0 100%;
    }
    85%,95%{
        background-position: 0 75%;
    }
    100%{
        background-position: 0 100%;
    }
}

/* pc到移动端  适配 css样式下面覆盖上面*/
@media only screen and (max-width: 480px){
    .baymax:before,.baymax:after{
        top: -4em;
        width: 8em;
        height: 8em;
    }

    .baymax:before{

        left: -5em;
    }

    .baymax:after{
        right: -5em;
    }
}
